The present invention relates to a composed projectile for subcalibre, in particular fine calibre ammuniton, comprising a sabot, a projectile and a driving speculum which, when present in an ammunition is suitable for firearms such as personal defence weapons (PDW), such as pistols, machine guns, but also automatic weapons of carbine type, as well as light support weapons. Further, the invention relates to a cartridge containing such a composed projectile, process for the manufacture of such a composed projectile, as well as projectile.
The object of the present invention is to obtain a composed projectile to be used preferably in a subcalibre ammunition of firearms and lighter offensive weapons, which ammunition meets great demands on performance with regard to penetration ability, range of fire and efficacy in the target.
Further objects are to meet environmental demands such as lowest possible discharge of toxic heavy metals, lowest possible weight, and possibility to use such ammunition without substantial changes of weapon systems in present firearms such as machine guns, pistols, automatic carbines and light support weapons.
The technical problem today is to obtain a projectile which provides a high penetration ability and this can i.a., be achieved by having a high outlet speed and with high maintained speed in the trajectory as well as a high speed in the target, preferably over a large distance. Such demands can be met only mainly by a projectile having high load, i.e., large mass per cross sectional area.
The demands have thus been to obtain an ammunition which can replace 9 mm parabellum ammunition and similar short ammunition types with the ammunition having high load in spite of short length, i.e., high weight per cross sectional area in the moving direction, high penetration ability, high impact energy in the target; short trajectory times with a fiat trajectory, and preferably, a high projectile speed in the target.
Standard ammunition is a type of ammunition, which is used by several weapons in a military unit. Today a military fighting unit uses a number of ammunition types due to the use of different types of weapons, such as pistols, machine guns, sniper weapons, light support weapons and automatic carbines, whereby 9 ram, 5.56 mm, and 7.62 mm ammunition types are available. If one can solve the technical problem discussed herein with standard ammunition, it would be highly desirable. From a logistic point of view one should have as few types of ammunition as possible and a desire is thereby to have as few ammunition types as possible to distribute to different units. If it would be possible to have the same ammunition in the pistol, which is carried by staff personal as in the automatic carbine, which is worn by soldiers in the front lines of the fighting unit, much would have been accomplished.
The 9 mm ammunition has been use for a long time and in particular to matching guns and pistols which are so called firearms of the type called personal defiance weapons (PDWxc3x97Personal Defense Weapon).
The drawback with 9-mm ammunition is that it has only a working range, which is about 200 m whereupon the spreading and ballistics make hits less sure. Due to the soft core of the projectile, large cross sectional area and low impact energy a 9-mm projectile will not pass through modern body shields. The lack of penetration ability provides for the fact that the projectile does not penetrate a modern body shield even after the weapon muzzle.
The present sabot bound projectiles for firearms, of the types mentioned above, have not been able to meet these great demands raised on ballistics and accuracy in firing due to different factor such a lack of support of the projectile by the sabot, and a inferior balance in the trajectory due to deficient separation between projectile and sabot.
U.S. Pat. No. 5,175,394 describes an arrangement for a low pressure cartridgexe2x80x94shot gun cartridge with about 80 MPaxe2x80x94where the pressure graph rapidly decreases and where the density of the projectile is not intended to exceed 11.4 (the density of lead). Further, no rotation is transferred to the projectile from the smooth bore. In order to be able to transfer acceleration from a sabot to a projectile this must have a very particular form having a pronounced waist where the sabot will obtain enough large attack-surface against the projectile. This specific design of the projectile has nothing in common to the present invention where completely different demands are made on the composed projectile, i.e. sabot and projectile.
EP-A-0 375 312 relates to a very ambitious construction what regard the application of fine calibre but does, in no way fulfil the requirement of minimal elongation besides the projectile of its own length. There is only an isolated termxe2x80x94high-density metalxe2x80x94from a sentence that has resemblance whatsoever with the present invention.
U.S. Pat. No. 4,653,404 relates to a construction, which requires a relatively thick bottom/supporting disc of the sabot behind the projectile. The contact area of the sabot against the projectile is restricted to the cylindrical jacket surface which, moreover, is broken by the splitting indents. This leads to an unprotected projectile point, which moreover creates a feeding problem in automatically charged weapons. Further the risk of projectile oscillation in the barrel having this short guidance, which can give troublesome effects not only on the trajectory, but also on the barrel. This is well known problem in the circuit of people skilled in the art using this construction with regard to the splitting of the sectors, which supposes that the material breaks completely symmetrically in order not to disturb the projectile at the separation. The latter is not the least important at strongly shifting temperature conditions. The supporting disc has to be applied already at the moulding of the sabot, which apparently makes the product more expensive and reduces production capacity.
U.S. Pat. No. 5,339,743 is apparently intended for a low-pressure system such as a shotgun. However, it is stated on unknown grounds, that the sabot with its projectile requires and obtains a rotation transferred from the barrel. In col. 2, line 17 it is stated the xe2x80x9ccopper slugxe2x80x9d whereby thus it is said that the material of the projectile is copper having a substantially lower density than the preferred projectile of the present invention. A further aid to help the sabot to withstand the gas pressure is the two elements being placed between the driving charge and the sabot. Such aids are not necessary at the present invention, which further reduces the cost in connection with the production, furthermore it prolongs the projectile.
It has now surprisingly turned out possible to be able to solve this problem by means of the present invention which is characterized in that the cartridge comprises a projectile made of a metallic material, preferably of high density, and that the length of the composed projectile does not substantially exceeds the length of the projectile.
Further characteristics are evident from the accompanying claims.
By means of the present invention shorter projectiles can be obtained which in the end can make it possible to create a more compact, shorter cartridge which in turn can lead to a more compact, lighter weapon.
By means of the present invention the use of high density metal materials in a projectile of a cartridge is made possible which projectile seen from a load point of view at comparable normal values has a form which is better than the basic form, has a V0, i.e., speed at the muzzle which exceeds the speed of said type of ammunition, has a V400 which exceeds the one of said ammunition type, has a E0, i.e., hitting energy at the muzzle which exceeds the one of said ammunition type, and a E400 which exceeds the one of said ammunition type as well. By means of the invention one can fire projectiles having a high density which maintains speed and energy. The high-density favours reduced speed reduction.
The invention will be described more in detail in the following with reference to the accompanying drawing, which shows a preferred embodiment, however, without being restricted thereto.
FIG. 1 shows a cross-section along the longitudinal axis of the upper part of a cartridge having a composed projectile in accordance with the present invention;
FIG. 2 shows a side view of a sabot used in a composed projectile in accordance with the present invention;
FIG. 3 shows a sabot according to FIG. 2 in a cross-section along its longitudinal axis;
FIG. 4 shows a sabot according to FIG. 2 in a perspective view;
FIG. 5 shows a side view of the parts of a composed projectile;
FIG. 6 shows a side view of a composed projectile according to the invention;
FIG. 7 shows the composed projectile according to FIG. 6 in a cross-section along its longitudinal axis;
FIG. 8 shows a side view of the projectile according to the invention;
FIG. 9 shows a view from behind of the projectile according to FIG. 8;
FIG. 10 shows a perspective view at an angle from behind of the projectile according to FIG. 8;
FIG. 11 shows a driving speculum contained in the composed projectile in a cross-section through its longitudinal axis;
FIG. 12 shows the driving speculum according to FIG. 11 seen in a perspective view from above; and
FIG. 13 a composed projectile with its casing during a firing event.